Temporins constitute a family of antimicrobial peptides that are mostly effective against gram-positive bacteria (including some antibiotic-resistant strains), and they have also been shown to affect some strains of gram-negative bacteria, fungi, and protozoa.1,2 Temporins are among some of the smallest antimicrobial peptides discovered, being only 10 to 13 amino acids long and having a low number of positively charged amino acids.1 Active Temporins tend to have a slight cationic character, are amidated at the C-terminus, and adopt an alpha-helical conformation.3Originally isolated from skin secretions as an innate immune response of the European red frog, Rana temporaria, various Temporins have also been discovered from other Rana species.3 Their unique properties, such as the ability to disturb the bacterial membrane and cause leakage of molecules, make it difficult for pathogen-resistance to develop.3,4 Temporins show a diverse array of activites, including the ability to induce hemolysis and migration of immune system cells.5,6 They are also capable of selective lysis of cancer cells due to the presence of anionic phospholipids found in both tumor and bacterial membranes.11. Mangoni, M. et al. J Biol Chem280, 984 (2005). 2. Wade, D. et al. FEBS Lett479, 6 (2000).3. Mangoni, M. et al. Eur J Biochem267, 1447 (2000)4. Mangoni, M. Cell Mol Life Sci63, 1060 (2006).5. Chen, Q. et al. J Immunol173, 2652 (2004).6. Wade, D. et al. Protein Pept Lett9, 533 (2002).